Please do not double post the same question.
There can be multiple factors for this error. 8Gb (HD space has nothing to do with this) is really the minimum amount for AC but the main ones:
1. File Size, specifically polygon count
2. Rendering Settings, image size and quality
You have not specified an OS but regardless these are the troubleshooting steps to try:
1. Close everything do a restart and try again and/or
2. Choose a smaller image size and/or
3. Choose a different rendering preset, and/or
4. Define a smaller rendering area using the marquee, and/or
5. Turn off all unnecessary layers
eduardo rolón AIA NCARB
Another of the forum moderators.
Macbook Pro M1 Max 64GB ram
OS X 10.XX latest
AC26 US/INT -> AC08
Puerto Rico, BVI, Miami